Vol 38, No 6 (2018)

Analytical evaluation of the flammability of alternative and blended fuels is considered. A method is proposed for determining the cetane number and ignition delay for fuels and the combustion characteristics in diesel engines.

Regulation in the mechatronic system of a DUO-300 rolling mill is investigated. The dynamics of an electric drive with a predictive PI controller in the current loop is analyzed. Methods are proposed for damping of self-oscillation and decrease in dynamic loads within the mechatronic system.

The resistance of single-carbide alloys with modified binder to high-temperature gas corrosion is investigated. Increase in the cobalt and molybdenum content in the hard alloys decreases their stability while adding iron and copper to the cobalt binder, along with a small quantity of titanium (up to 2%), improves the stability and performance of the alloys.

The use of ultrasound in cutting plastics, synthetic fabrics, and polymer films is considered. A practical configuration is outlined, and the benefits of ultrasound in cutting are presented. The influence of the parameters in ultrasonic cutting on the productivity and the quality of the machined polymer is analyzed.

The frictional coefficients at the front and rear surfaces of a VK6 hard-alloy cutter with experimental nano- and microcrystalline CVD diamond coatings applied in microwave plasma are determined by extrapolation to zero cut-layer thickness. It is found that, for diamond coatings with a single microcrystalline layer and those with both a microcrystalline layer and a nanocrystalline layer, the frictional coefficients are less than for an uncoated hard-alloy cutter and also for a cutter with a Sandvik diamond coating.

Assessment of the effectiveness of personnel management at the United Aircraft Corporation (UAC) is considered. Three groups of personnel-management functions are identified. Their significance is analyzed in the light of the organization’s life cycle. Assessment of the outsourcing of functions on the basis of functional and cost analysis is proposed.

Parametric synthesis of a two-mass supply drive is considered, in the case where one mass is the moment of inertia of the drive’s rotating part, while the other is the reduced moment of inertia of the drive’s linearly moving part. The elastic coupling between the masses determines the axial rigidity of the drive. In synthesis, the parameters of the electromechanical system are determined by setting the coefficients of the characteristic polynomial equal to the coefficients of the polynomial approximating an ideal low-frequency filter.

An adjustable reamer permitting scratch-free extraction from the machined hole is described. Formulas for the geometric parameters of reamers with diameters in the range 32–140 mm are presented. The results required for the development of design documentation are derived.

The applicability of electrolytic plasma surface polishing to complex components produced by selective laser melting (SLM) is analyzed. By electrolytic plasma polishing by electrolyte spraying, the surface quality of components produced by SLM may be improved. This technology is found to decrease the surface roughness from R_a = 5.6 μm to 1.4 μm. The optimal pressure of the electrolyte jet is 0.02–0.05 MPa. At high pressures, the process becomes unstable. By electrolytic plasma polishing on the basis of electrolyte jets, uniform external and internal surface roughness of components produced by SLM may be ensured.